Semiconductor device having groove-shaped via-hole

Abstract

The semiconductor device has insulating films 40, 42 formed over a substrate 10; an interconnection 58 buried in at least a surface side of the insulating films 40, 42; insulating films 60, 62 formed on the insulating film 42 and including a hole-shaped via-hole 60 and a groove-shaped via-hole 66a having a pattern bent at a right angle; and buried conductors 70, 72a buried in the hole-shaped via-hole 60 and the groove-shaped via-hole 66a. A groove-shaped via-hole 66a is formed to have a width which is smaller than a width of the hole-shaped via-hole 66. Defective filling of the buried conductor and the cracking of the inter-layer insulating film can be prevented. Steps on the conductor plug can be reduced. Accordingly, defective contact with the upper interconnection layer and the problems taking place in forming films can be prevented.

What is claimed is: 
     
       1. A semiconductor device comprising:
 a rectangular semiconductor substrate including a semiconductor circuit region and four corners; 
 a first insulating film formed above the rectangular semiconductor substrate; 
 a first conductive layer formed in the first insulating film, 
 a second insulating film formed above the first insulating film; and 
 a plurality of guard rings surrounding the semiconductor circuit region; 
 wherein: 
 each of said guard rings includes a groove-shaped via-hole formed in the second insulating film; 
 the groove-shaped via-hole includes a pattern bent twice each time at an angle of larger than 90° at each of the four corners; 
 the pattern is bent totally at 90° at each of the four corners of the rectangular semiconductor substrate; and 
 a conductor formed in the groove-shaped via-hole and connected to the first conductive layer. 
 
     
     
       2. The semiconductor device according to  claim 1 , wherein the pattern is bent twice each time at a same angle of larger than 90°. 
     
     
       3. The semiconductor device according to  claim 1 , the first conductive layer includes a pattern bent in substantially same way as the pattern of the groove-shaped via hole at each of the four corners. 
     
     
       4. The semiconductor device according to  claim 1 , wherein the first insulating film is SiC based film. 
     
     
       5. The semiconductor device according to  claim 1 , wherein the first insulating film is SiOC based film. 
     
     
       6. The semiconductor device according to  claim 1 , wherein the first insulating film is SiOC film/SiC film-based inter-layer insulating film. 
     
     
       7. The semiconductor device according to  claim 1 , wherein the first insulating film includes silicon, carbon and oxygen. 
     
     
       8. The semiconductor device according to  claim 1 , wherein the second insulating film is SiC based film. 
     
     
       9. The semiconductor device according to  claim 1 , wherein the second insulating film is SiOC based film. 
     
     
       10. The semiconductor device according to  claim 1 , wherein the second insulating film is SiOC film/SiC film-based inter-layer insulating film. 
     
     
       11. The semiconductor device according to  claim 1 , wherein the second insulating film includes silicon, carbon and oxygen. 
     
     
       12. The semiconductor device according to  claim 1 , wherein the first insulating film and the second insulating film include silicon, carbon and oxygen.